721-04-0Relevant articles and documents
Cu(i)-Catalyzed asymmetric intramolecular addition of aryl pinacolboronic esters to unactivated ketones: Enantioselective synthesis of 2,3-dihydrobenzofuran-3-ol derivatives
Ni, Chunjie,Gao, Jihui,Fang, Xianjie
, p. 2654 - 2657 (2020)
An (S,S)-QuinoxP?-supported Cu(i) catalyst has been disclosed for highly enantioselective intramolecular addition of aryl pinacolboronic esters to unactivated ketones under mild reaction conditions. This protocol showcases a broad substrate tolerance and allows access to various chiral 2,3-dihydrobenzofuran-3-ol derivatives in generally good yields with excellent enantioselectivities.
Mild selective oxidative cleavage of lignin C-C bonds over a copper catalyst in water
Hu, Yuzhen,Li, Song,Ma, Longlong,Wang, Chenguang,Yan, Long,Zhang, Qi,Zhang, Xinghua,Zhao, Xuelai
supporting information, p. 7030 - 7040 (2021/09/28)
The conversion of lignin into aromatics as commodity chemicals and high-quality fuels is a highly desirable goal for biorefineries. However, the presence of robust inter-unit carbon-carbon (C-C) bonds in natural lignin seriously impedes this process. Herein, for the first time, we report the selective cleavage of C-C bonds in β-O-4 and β-1 linkages catalyzed by cheap copper and a base to yield aromatic acids and phenols in excellent yields in water at 30 °C under air without the need for additional complex ligands. Isotope-labeling experiments show that a base-mediated Cβ-H bond cleavage is the rate-determining step for Cα-Cβ bond cleavage. Density functional theory (DFT) calculations suggest that the oxidation of β-O-4 ketone to a key intermediate, i.e., a peroxide, by copper and O2 lowers the Cα-Cβ bond dissociation energy and facilitates its subsequent cleavage. In addition, the catalytic system could be successfully applied to the depolymerization of various authentic lignin feedstocks, affording excellent yields of aromatic compounds and high selectivity of a single monomer. This study offers the potential to economically produce aromatic chemicals from biomass.
1,3-Dibromo-5,5-dimethylhydantoin (DBH)/DMSO mediated oxidative difunctionalization of styrenes: Microfluidic synthesis of pentafluorophenoxy ketone
Xu, Jia,Hua, Jiawei,Bian, Mixue,Li, Yuguang,He, Wei,Yang, Zhao,Liu, Chengkou,Fang, Zheng,Guo, Kai
supporting information, (2021/02/27)
A practical and mild synthesis of pentafluorophenoxy ketone in a continuous flow microfluidic reactor has been developed through 1,3-Dibromo-5,5-dimethylhydantoin (DBH)/DMSO mediated oxidative coupling of styrenes with pentafluorophenol. Moreover, a series of pentafluorophenoxy ketone products were provided in moderate to good yields under metal-free conditions. A magnifying continuous flow system was erected to verify the appliance of this method.
